textproduct: Quad Cities

KEY MESSAGES

- The persistent blocking pattern across the CONUS is forecast to continue before breaking down later this week and into the weekend, bringing a return of shower and storm chances (40-60%). However, widespread beneficial rainfall is unlikely.

- The recent lack of rain and overall limited rainfall coverage later this week is expected to result in an expansion of abnormally dry conditions, with increased chance of moderate drought developing.

SHORT TERM /THROUGH TUESDAY/

Issued at 147 PM CDT Mon Jun 1 2026

An omega blocking pattern aloft will maintain control over the central CONUS, with elongated troughing over the northern Rockies and New England regions. Given better forcing for showers and storms remaining to the south and west of our region, along with a large area of surface high pressure building in across the western Great Lakes, conditions should continue to be dry tonight through Tuesday. Temperatures tonight will be a bit cooler compared to this morning as lower dew point air and largely clear skies develop, with lows dipping to the lower to middle 50s - seasonal for this time of the year. Another day of temperatures warming to the lower 80s is expected for Tuesday.

LONG TERM /TUESDAY NIGHT THROUGH MONDAY/

Issued at 155 PM CDT Mon Jun 1 2026

Tuesday night-Wednesday...As the textbook omega block over the CONUS begins to break down, the trough over the Mid-Atlantic region pushes southward as high pressure anchors over the Great Lakes. This will keep our winds easterly at 5-10 knots through Wednesday evening and advect in some cooler, drier air into the CWA, so despite the ridging, temperatures will only be a few degrees above average with mostly clear skies.

Thursday-Saturday...The trough that has been stalled out over the Northern Rockies finally moves into the Northern Plains and south- central Canada, kicking the ridge over the Great Lakes southeastward and pulling a shortwave in the subtropical jet northeastward into the Central Plains. Low pressure will deepen along the Front Range and near the North Dakota-Canada border as our winds shift out of the south, advecting in warmer, moist air from the Gulf. PWATs are forecast to increase by 0.75 to 1 inch Thursday morning into Friday morning. As a cold front progresses across the Northern Plains and bands of shear vorticity are advected into Upper Mississippi River Valley, rain chances increase to 40-60% Friday into Saturday, but there is uncertainty on the precipitation amounts through Saturday, with guidance suggesting a range from a few hundredths to half an inch. This also translates to uncertainty in high temperatures where cloud cover and rainfall could keep highs closer to 80 or warm air advection could bolster highs closer to 90. Currently, the LREF has a 20-50% chance of highs exceeding 85 Thursday through Saturday. Regardless though, lows will likely (60-80% chance) be 5-10 degrees above average Friday and Saturday as dewpoints are expected to climb into the mid-60s.

In terms of severe weather, current GEFS ensembles has a 40-70% chance of SBCAPE values exceeding 1000 J/kg, but the displaced trough to the north should limit the surface to 500mb effective bulk shear to only 25-30 knots. While this is modest instability and shear, a few organized storms cannot be ruled out.

Sunday...Another shortwave in the subtropical jet stream is pulled northeastward into the Central Plains by a longwave trough digging into the western CONUS. With PWATs already high from the previous system, PoPs once again increases with the LREF giving 60-80% coverage. While it is too far out to accurately forecast precipitation amounts, the ingredients are there for excessive rainfall, especially with dewpoints potentially exceeding 70 degrees (40-60% chance).

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 549 PM CDT Mon Jun 1 2026

Clear or clearing skies will continue this evening as high pressure moves into the area from the north. The wind flow will decrease this evening and remain east/northeasterly at 5-10kts. Excellent visibility will continue with such dry air in place.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.